[Ocfs2-devel] vfs-scale, nd->inode after __do_follow_link()

[J.H.]

Nick,

Just thought I'd let you know - with, or without, the vfs-scale code
that you've got I'm getting this:

[  472.666054] ------------[ cut here ]------------
[  472.670724] kernel BUG at fs/dcache.c:1358!
[  472.674944] invalid opcode: 0000 [#1] SMP
[  472.679112] last sysfs file:
/sys/devices/system/cpu/cpu15/cache/index2/shared_cpu_map
[  472.687105] last /proc..net open:  /proc/7687/net/route
[  472.695829] last /proc..net close: /proc/7687/net/route
[  472.704490] CPU 0
[  472.706361] Modules linked in: ocfs2 mptctl mptbase ipmi_devintf drbd
lru_cache nfsd lockd nfs_acl auth_rpcgss sunrpc ocfs2_dlmfs
ocfs2_stack_o2cb ocfs2_dlm ocfs2_nodemanager ocfs2_stackglue configfs
8021q garp stp llc ip6t_REJECT nf_conntrack_ipv6 nf_defrag_ipv6
ip6table_filter ip6_tables ipv6 xfs exportfs serio_raw iTCO_wdt bnx2
microcode hpwdt iTCO_vendor_support ipmi_si power_meter ipmi_msghandler
pcspkr hpilo i7core_edac edac_core shpchp hpsa radeon ttm drm_kms_helper
drm i2c_algo_bit i2c_core [last unloaded: speedstep_lib]
[  472.776643]
[  472.782039] Pid: 2716, comm: httpd Tainted: G        W   2.6.37+ #4
/ProLiant DL380 G6
[  472.793922] RIP: 0010:[<ffffffff8113ed85>]  [<ffffffff8113ed85>]
d_set_d_op+0x13/0x5e
[  472.793931] RSP: 0018:ffff8807d4f87c08  EFLAGS: 00010282
[  472.793933] RAX: 0000000000000000 RBX: 0000000000000000 RCX:
0000000000000000
[  472.793936] RDX: 0000000000000246 RSI: ffffffffa04dc880 RDI:
ffff8803cf7bcbd0
[  472.793939] RBP: ffff8807d4f87c08 R08: ffffffffa0491049 R09:
0000000000000001
[  472.793942] R10: ffff8803fc70c778 R11: ffff880700000000 R12:
ffff8803cf737000
[  472.793945] R13: ffff8803cb822120 R14: ffff8803cb821460 R15:
ffff8803cf7bcbd0
[  472.793949] FS:  00002b86adeee660(0000) GS:ffff8800dd400000(0000)
knlGS:0000000000000000
[  472.793952] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  472.793955] CR2: 00002b86ad2c4888 CR3: 00000007d4f75000 CR4:
00000000000006f0
[  472.793958] DR0: 0000000000000000 DR1: 0000000000000000 DR2:
0000000000000000
[  472.793961] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7:
0000000000000400
[  472.793964] Process httpd (pid: 2716, threadinfo ffff8807d4f86000,
task ffff8807d4e723b0)
[  472.793967] Stack:
[  472.793968]  ffff8807d4f87d28 ffffffffa04aac62 ffff8803ddabfe30
ffff8803cb820e78
[  472.793973]  ffff8803fbc38000 ffff8803cb820ee8 00000000a0491177
ffff8803f36cd000
[  472.793978]  00008000d4f87c98 ffff8803fbc38000 ffff8803cf727d90
0000000000000000
[  472.793983] Call Trace:
[  472.794010]  [<ffffffffa04aac62>] ocfs2_mknod+0xb0f/0xd3e [ocfs2]
[  472.794032]  [<ffffffffa04aaeb9>] ocfs2_create+0x13/0x15 [ocfs2]
[  472.794036]  [<ffffffff811392b7>] vfs_create+0x70/0x92
[  472.794041]  [<ffffffff81139fdc>] do_last+0x163/0x2e0
[  472.794045]  [<ffffffff8113a460>] do_filp_open+0x307/0x6f1
[  472.794050]  [<ffffffff81145394>] ? alloc_fd+0x3b/0x193
[  472.794055]  [<ffffffff81082e33>] ? lock_release+0x19a/0x1a6
[  472.794059]  [<ffffffff811454da>] ? alloc_fd+0x181/0x193
[  472.794063]  [<ffffffff8112d1f6>] do_sys_open+0x60/0xf2
[  472.794068]  [<ffffffff814a7aef>] ? trace_hardirqs_on_thunk+0x3a/0x3f
[  472.794072]  [<ffffffff8112d2a8>] sys_open+0x20/0x22
[  472.794077]  [<ffffffff8100ac42>] system_call_fastpath+0x16/0x1b
[  472.794079] Code: a9 ff 03 00 00 74 08 81 0b 80 00 00 00 eb 06 81 23
7f ff ff ff 5b c9 c3 55 48 89 e5 0f 1f 44 00 00 48 83 bf a8 00 00 00 00
74 02 <0f> 0b 8b 07 f6 c4 f0 74 02 0f 0b 48 85 f6 48 89 b7 a8 00 00 00
[  472.794112] RIP  [<ffffffff8113ed85>] d_set_d_op+0x13/0x5e
[  472.794116]  RSP <ffff8807d4f87c08>
[  472.794387] ---[ end trace 04b2ab2cb7dc3150 ]---

I only mention this as the ocfs2 folks suggested running your code might
solve that problem.  That said I'm going to punt this back over to the
ocfs2 folks for further review, as the bug makes ocfs2 completely
unusable on 2.6.37+

- John 'Warthog9' Hawley